Add 'error' property to exceptions thrown via Worker::importScripts.

Source/bindings/v8/V8ErrorHandler.h

Index: Source/bindings/v8/V8ErrorHandler.h
diff --git a/Source/bindings/v8/V8ErrorHandler.h b/Source/bindings/v8/V8ErrorHandler.h
index 90fdf5f81a0954f2b17f6f9303c9f7c115f792fb..92246d3f136dc6eb163f8e173fda46e0d0dd1f90 100644
--- a/Source/bindings/v8/V8ErrorHandler.h
+++ b/Source/bindings/v8/V8ErrorHandler.h
@@ -37,6 +37,9 @@
 
 namespace WebCore {
 
+class ErrorEvent;
+class Frame;
+
 class V8ErrorHandler : public V8EventListener {
 public:
     static PassRefPtr<V8ErrorHandler> create(v8::Local<v8::Object> listener, bool isInline)
@@ -44,6 +47,8 @@ public:
         return adoptRef(new V8ErrorHandler(listener, isInline));
     }
 
+    static void storeExceptionOnErrorEventWrapper(ErrorEvent*, v8::Handle<v8::Value>, v8::Isolate*);
+
 private:
     V8ErrorHandler(v8::Local<v8::Object> listener, bool isInline);